1. Which of the following is NOT a function of the cardiovascular system?

A. Transporting oxygen to cells
B. Maintaining blood pressure
C. Carrying waste products to the kidneys for removal
D. Initiating the immune response

Correct answer: D

Rationale: The cardiovascular system is responsible for transporting oxygen to cells (option A), maintaining blood pressure (option B), and carrying waste products to the kidneys for removal (option C). However, initiating the immune response (option D) is not a function of the cardiovascular system. The immune response is primarily carried out by the immune system, which includes organs like the spleen and lymph nodes. While the cardiovascular system does play a role in immune function by transporting immune cells and antibodies, it is not responsible for initiating the immune response. Therefore, option D is the correct answer.

2. How does the potential energy of an object change when it is compressed?

A. Potential energy decreases
B. Potential energy increases
C. Potential energy remains constant
D. Potential energy becomes zero

Correct answer: b

Rationale: When an object is compressed, it stores potential energy due to its altered position or configuration.

3. Which element has the highest melting point of any element?

A. Tungsten
B. Iron
C. Platinum
D. Carbon

Correct answer: D

Rationale: Diamond's strong covalent bonds between carbon atoms make it incredibly resistant to heat and pressure, giving it the highest melting point.

4. Sunscreen protects the skin from harmful ultraviolet (UV) rays by

A. Reflecting UV rays away from the skin
B. Absorbing UV rays and converting them to heat
C. Blocking UV rays completely
D. Stimulating melanin production

Correct answer: B

Rationale: The correct answer is B: Absorbing UV rays and converting them to heat. Sunscreen contains ingredients that act as filters to absorb UV radiation before it reaches the skin. These filters then convert the UV rays into a less harmful form of energy, usually heat, which is then released from the body. This process helps prevent UV radiation from damaging the skin cells and causing sunburn or long-term skin damage. Reflecting UV rays away from the skin (A) and blocking UV rays completely (C) are not accurate functions of sunscreen. Additionally, stimulating melanin production (D) is not a direct way in which sunscreen protects the skin from UV rays.

5. What is the term for a solution with a pH value less than 7?

A. Acidic
B. Neutral
C. Alkaline
D. Basic

Correct answer: a

Rationale: Solutions with a pH less than 7 are acidic. The other choices do not accurately describe solutions with a pH less than 7.

6. A car is traveling on a curved road. What force keeps the car moving along the curved path?

A. Gravitational force
B. Normal force from the road
C. Air resistance
D. Friction between the tires and the road

Correct answer: D

Rationale: In this case, static friction acts between the tires and the road, providing the centripetal force required to keep the car moving in a circle even though it's traveling in a straight line relative to the ground.